A step towards quantum electronics

Work of physicists at the University of Geneva (UNIGE), Switzerland, and the Swiss Federal Institute of Technology in Zurich (ETH Zurich), in which they connected two materials with unusual quantum-mechanical properties through a quantum constriction, could open up a novel path towards both a deeper understanding of physics and future electronic devices.

The researchers work with atoms that are trapped in laser beams and thus isolated from any external disturbance. Lasers are also used to cool the atoms to temperatures lower than those found anywhere else in the entire Universe. These ‘ultracold’ temperatures then enable creating clean materials that possess intriguing quantum-mechanical properties, such as unusual superconductivity.

The experimental team in Zurich, led by Tilman Esslinger and Jean-Philippe Brantut, has now overcome the challenges to efficiently transport ultracold atoms between two quantum superconductors with strong interactions through a single quantum point, a so-called quantum point contact. “With this new quantum connection, we can now reveal new effects in these superconducting quantum systems. It is a fundamental breakthrough in the way we can use quantum physics with cold atoms,“ says Thierry Giamarchi, from UNIGE's Faculty of Science.